Qt on Raspberry Pi. Jeff Tranter Integrated Computer Solutions (ICS) Qt Developer Days

Transcription

1 Qt on Raspberry Pi Jeff Tranter Integrated Computer Solutions (ICS) Qt Developer Days 2012

2 Agenda What is the Raspberry Pi? Raspberry Pi Foundation Hardware Software QtonPi Distribution QtonPi Device Program Qt 4 on Raspberry Pi Qt 5 on Raspberry Pi

3 Agenda (continued) Input Devices - Mouse, Keyboard Output Devices and Touchscreen Major Competitors Misc. Issues Areas Of Future Development Demo References Summary

4 What is the Raspberry Pi? "The lack of programmable hardware for children the sort of hardware we used to have in the 1980s is undermining the supply of eighteen year olds who know how to program, so that's a problem for universities, and then it's undermining the supply of 21 year olds who know how to program, and that's causing problems for industry." - Co-founder Eben Upton in 2012

5 Raspberry Pi Foundation Non profit British charity Promotes basic computer science in schools Small: day to day work done by one full-time paid employee and volunteers Manufacturing and sales licensed to distributors: Element 14 and RS

6 What is the Raspberry Pi? Project originally started in 2006 Eventually decided on ARM architecture Alpha boards Aug 2011 Beta boards Dec 2011 Sales launched February 2012 First batch of 10,000 boards in Mar 2012

7 What is the Raspberry Pi? Two licensed manufacturers/distributors Initially unable to keep up with orders Two million people registered interest in pre-orders As of early July 2012: production 4,000 per day, approx 200K shipped Backlog now down to a few weeks Most manufacturing now done in the UK

8 What is the Raspberry Pi?

9 What's With the Name? Nostalgia: a number of early home computers had "fruit" names, e.g. Apple, Apricot, Tangerine PI is from "Python Interpreter", the official programming language for the Raspberry Pi

10 Hardware

11 Hardware Credit card sized computer CPU: Broadcom BCM2835 SOC 700MHz ARM11 with floating point Videocore 4 GPU capable of BluRay quality 1080p30 video using H.264 at 40MBits/s OpenGL ES2.0 and OpenVG SD card for mass storage (can also use USB after booting) Model A: 256MB RAM, 1 USB port (not yet shipping) Model B: 512MB* RAM, 2 USB ports, Ethernet

12 Hardware Composite and HDMI video out Sound output over HDMI and 3.5mm audio jack; can use USB microphone for input Header with GPIO ports Powered by 5V over micro USB (2.5W/3.5W. Could use battery, i.e. 4 AA cells. Power by USB port not recommended.) No RTC (gets time from network) Memory not expandable

13 Hardware Retail price US$25 (Model A) / US$35 (Model B) Board only: typically add HDMI monitor, SD card, USB keyboard and mouse, power supply Some users may use television and second hand keyboard/mouse to save on cost Hardware schematics available

14 Input Devices - Mouse, Keyboard USB mouse and keyboard supported Can use (powered) hub if more than two USB devices needed

15 Output Devices and Touchscreen HDMI and composite video out Can use DVI or VGA monitor with adaptor Standard touch screen monitors with HDMI should work out of box if they emulate a USB mouse Chalkboard Electronics has compatible 10 inch touchscreen with HDMI to LVDS interface board Dell 2220 touch screen monitor (needs modified kernel)

16 Other Hardware GPIO, serial, SPI, I 2 C, JTAG ports brought out on 26-pin connector P1 use caution if used directly as no protection from overvoltage, etc. MIPI CSI-2 (Camera Serial Interface) on connector S5 DSI (Display Serial Interface) on connector S2 for driving LCD (no drivers currently) Rev 2 board makes some small changes

17 Other Hardware

18 Other Hardware Official camera module: Approx. $25 5 MP images and video Attaches to CSI port via ribbon cable GPIO expansion boards: AdaFruit Pi Cobbler, AdaFruit Pi Plate, GertBoard LCD displays Third party cases Many more to come

19 Software Linux-based recommended distro is Debian-based Raspbian "Wheezy" (uses hardware FP) Several other Linux distros supported GPU code was proprietary but open sourced in Oct Other operating systems: RISC OS (Acorn), Android, BSD, Plan 9, AROS, Open WebOS, etc.

20 Software Currently aimed mostly at developers Preferred language for educational apps is Python Will eventually include applications like games and development tools for kids including BASIC, Python Unlikely to Run Windows 8 (needs newer ARM CPU) Can't run Windows apps using WINE since not x86

21 Raspbian Distribution Currently the preferred distribution Based on upcoming Debian 7.0 Wheezy release Optimized for Raspberry Pi hardware LXDE - Lightweight X11 Desktop Environment Uses hardware floating point in ARM chip Over 35,000 software packages

22 QtonPi Distribution Qt 5-focused distribution SDK (Qt Creator) with development tools SD card image Fedora based No longer maintained, Qt 5 packages are now in Debian Wheezy beta and soon in Raspbian

23 Other Distributions AdaFruit Occidentalis distribution for teaching electronics AdaFruit WebIDE: browser based IDE that runs on desktops ARCH Linux ARM Soft-float Debian Wheezy

24 QtonPi Device program 400 boards ordered by Nokia and partners like ICS in late 2011 Allocated to Qt developers who were qualified with project ideas Delivery was delayed by move to using licensed hardware distributors Shipped to developers and partners in August 2012

25 Qt 4 on Raspberry Pi Packages available on Debian Wheezy beta and Raspbian Doesn't make use of graphics hardware acceleration (no OpenGL) Runs okay in my experience Focus of development is on Qt 5 where Scene Graph pushes more work to GPU

26 Qt Mobility (Qt 4) Qt add-on used by some applications Not available as a package Was not ported to Raspberry Pi per se Builds from source without changes Some modules are not applicable (e.g. phone-specific) Use latest source from git as the 1.2 release is getting old and has some compile issues In Qt 5 Mobility becomes optional Qt 5 modules

27 Qt 5 on Raspberry Pi Nokia sponsored work (QtonPi) since late 2011 Can use Wayland and hardware accelerated cursor Uses GStreamer for multimedia H.264 only free HD video format supported on Pi due to licensing issues Hardware similar to some Nokia phones? Packages currently in Debian Wheezy beta, moving to Raspbian Packaging of QtMultimedia and QtWebKit being worked on

28 Qt 5 on Raspberry Pi See qt-project.org Wiki Bakeqtpi script to cross-compile Qt 5 on desktop Qt Creator can be used to build (cross-compile) and deploy

29 EGLFS Qt 5 on Raspberry Pi normally uses EGLFS back end Uses OpenGL/ES for rendering Runs full screen, no window manager, one application instance, does not use X11 Wayland compositor backend can play nicely with X11 and window managers while still using OpenGL/ES xcb backend for X11 currently has no OpenGL support (needed for Qt Quick 2)

30 Raspberry Pi Competitors For embedded development BeagleBoard (more expensive) Arduino (simpler OS) VIA APC (Android) Many others coming...

31 Misc Issues Wheezy includes "omxplayer" video player application Foundation sells licenses for commercial codecs: VC-1 (Microsoft) and MPEG-2 RAM is shared between CPU and GPU. Can adjust how it is split (See Wiki and raspi-config program) Compiling on the Pi is slow. Can cross-compile on a Linux desktop. See Wiki for details. QEMU emulator to emulate Raspberry Pi on Windows or Linux desktop Hardware compatibility issues with some SD cards (should be mostly resolved now)

32 Misc Issues Overclocking/overvoltage possible (up to 1 GHz) For more filesystem storage you can connect USB flash or hard drive Can use USB dongle for Wi-Fi if it has a suitable driver Official book: Raspberry Pi User Guide Free monthly magazine: The MagPi Summer 2012 coding contest

33 Areas Of Future Development Port of Android 4.0 (already demoed) Model A Educational/consumer version with case, power supply, keyboard, etc. Third party add-ons like cases, touch screens, expansion boards

34 Demo

35 References

36 Summary Raspberry Pi is an extremely low cost computer that can be used for embedded Qt 5 development. Good reference platform for Qt 5 with Qt Quick 2 (QML scene graph) Needs volunteers to help develop the platform and applications.

37 The End Thank you very much for attending!

38 Q&A Questions?